Metal buckle



J. R. BEACH Oct. 31', 1967 METAL BUCKLE Filed April 12, 1965 I M @ZeacUnited States Patent 3,349,444 METAL BUCKLE John R. Beach, Elmhurst,Ill., assignor to Signode Corporation, a corporation of Delaware FiledApr. 12, 1965, Ser. No. 447,423 4 Claims. (Cl. 24-74) ABSTRACT OF THEDISCLOSURE A one-piece metal buckle as disclosed is formed from a lengthof rod stock to present a pair of crossbars at each end of the buckleoutline. Each pair of crossbars receives a strap end portion in areverse folded relationship to develop increased frictional holdingpower against strap pull out by presenting maximum surface contact areabetween the crossbars and the strapping. At each end, the inner wrap ofthe folded strap is impressed against one of the crossbars by the outerwrap, with additional holding power being developed by contact betweenthe inner and outer wraps.

This invention relates to buckles for use with nonmetallic strapping forsecuring opposite ends of a strap loop which is to be arranged in tautrelation about a package or other object that is to be tied.

Plastic strap or tape is now used in many instances where steel straphas been employed in the past and due to its elastic and resilientproperties finds many strapping applications for which steel strap isunsuitable.

The advent of non-metallic strap, in particular plastic strap, hasbrought with it the need for specialized connectors for securingopposite ends of the strap loop. The metal seals which requiremechanical crimping have not found universal application with plasticstrap and various types of buckles have been employed, which depend upondevelopment of mechanical, frictional engagement with the strap ends.Until the present time, the holding power of these buckles has beenunduly limited. This has been a limiting factor in the exploitation ofthe plastic strap field. In addition, with the use of smoother surfacedplastic straps, such as strapping of polypropylene, the slippery surfacecharacter of the strapping has made the buckle gripping factor even morecritical.

In accordance with the present invention, a buckle is providedexhibiting significantly improved holding power with respect to thestrap ends which are threaded through it. A feature of the invention isthe provision of a one-piece skeletal rod buckle for individuallyreceiving each of the opposite ends of a strap loop and establishing anincreased surface area of contact against the strap to maximizefrictional holding power.

Another feature of the invention is to provide an improved buckle-typestrap connector that is laterally open adjacent each end to facilitatestrap threading.

Still another feature of the invention is the provision of a buckle-typestrap connector having a symmetrical configuration to enable convenientuse in any orientation, both from the standpoint of ease of threadingand from the standpoint of effective frictional engagement.

Other and further features of the invention will be apparent from thefollowing description and claims, and are illustrated in theaccompanying drawings which show structure embodying preferred featuresof the present invention and the principles thereof, and what is nowconsidered to be the best mode in which to apply these principles.

In the accompanying drawings forming a part of the 3,349,444 PatentedOct. 31, 1967 figuration for the buckle; and

FIGURE 5 is an enlarged fragmentary diagrammatic cross-sectional Viewtaken through a buckle having opposite ends of the strap loop looselythreaded therein and having the areas of surface contact presented bythe buckle emphasized in heavy lines to demonstrate the principles whichcontribute to the significant improvement in holding power provided bythe buckle of this invention.

Referring now to the drawings, the typical application in which thebuckle of the present invention is employed is illustrated in FIGURE 1wherein a package or other object that is to be tied is designatedgenerally at 10 and is shown equipped with a strap loop 11 having itsopposite ends 12 and 13 individually threaded through opposite ends of abuckle-type connector 14. Arrangements of this general type are wellknown wherein the buckle 14 is formed of a bent wire rod ofsubstantially stable configuration, and wherein the strap 11 isnonmetallic and preferably of a plastic that exhibits tensile strengthand elastic recovery such that it assumes a taut, snug relation aboutthe object. The stability of the connection between each strap end andthe buckle depends upon the frictional relationships existing and whilevarious complex buckle configurations have been developed, there is needfor a buckle which is easily threaded at each end and which exhibitsresistance to distortion and, more importantly, a strong slip-proofengagement with the strap ends.

The buckle 14 is formed from a suitably bent onepiece metal rod,preferably of spring wire and preferably suitably surface-roughened andthereafter surfacecoated to increase its frictional properties, thoughthe invention is not limited to surface treating of the buckle. As isbest seen in FIGURE 4, the buckle is of generally rectangularconfiguration in plan outline and has a first set of strap engagingcrossbars 15 and 16 at one end and a second set of strap engagingcrossbars 17 and 18 at its opposite end. In the strap and bucklearrangement of FIGURES 1 and 5, the strap end 12 is shown threadedthrough the set of crossbars 15 and 16 and the strap end 13 is shownthreaded through the crossbars 17 and 18. These sets of crossbars arelocated in generally side by side relation to each other, and thecrossbars common to each set are located in generally side by siderelation to each other. Thus, it may be seen that the crossbar set 15and 16 is spaced from the crossbar set 17 and 18 in a direction endwiseof the buckle to define a common central opening 19 for passage of theopposite ends of the strap. Correspondingly, the crossbars 15 and 16 ofthe first set are spaced in a direction endwise of the buckle to definean intermediate opening 20 for passage of the strap end 12 while thecrossbars 17 and 18 are also spaced in a direction endwise of the buckleto define an intermediate opening 21 for passage of the strap end 13.

It may be noted that the first crossbar 15 constitutes a terminalportion of the rod and defines one extremity of the buckle outline, thatthe second crossbar 16 of the same set constitutes an intermediatesection of the rod, that the first crossbar 17 of the second setconstitutes another intermediate section of the rod, and that the secondcrossbar 18 of the second set constitutes an opposite terminal portionof the rod and defines an opposite end extermity of the buckle outline.

To complete the buckle, the rod has an endwise run 22 interconnectingcrossbars 15 and 17, another endwise run 23 interconnecting crossbars 16and 18, and a final endwise run 24 interconnecting the crossbars 16 and17. The endwise runs 22 and 23 are located on the same side of thebuckle and are partially overlapping and partially exposed in planoutline relation to each other to react one against the other forstablilizing the buckle configuration. The endwise run 24 is located onthe opposite side of the buckle. As may be observed in FIG- URE 3, therun 24 extends from the plane of the run 22 to the plane of the run 23.

It may be further noted from the drawing figures that the endwise runs22 and 23 are corresponding in length and symmetrical about a transversebuckle centerline such that the spacial relationship existing betweenthe crossbars 15 and 16 corresponds closely to the spacial relationhipexisting between the crossbars 17 and 18.

In the practice of the invention, each of the crossbars 15 to 18 andeach of the runs 22 to 24 are straight with adjacent ends of theseelements being integrally connected by substantially right-angle bendportions of the rod. This is the simplest form of buckle to fabricate,but it will be appreciated that the crossbars and endwise runs need notbe exactly straight so long as the essential relationships of thestructure are maintained.

In the structural embodiments having the general arrangement andconfiguration illustrated in the drawings, spring wire of 0.135 inchdiameter is employed with the central opening 19 having a dimension ofinch in the endwise buckle direction, and with each of the intermediateopenings 20 and 21 having a dimension of A3 inch in the endwise buckledirection. While round rod cross sections are illustrated herein,variations of the cross-sectional contour of the rod are contemplatedwhere circumstances so require and where the strap properties permit.

Two different configurations for the buckle are disclosed herein, thedifferences being apparent primarily from a consideration of the planoutline views of FIG- URES 4 and 4A. In the preferred configuration,illustrated in FIGURE 4, the endwise runs 22 and 23 are in differentvertical planes that are oppositely angled from a true lengthwisedirection through the buckle. Typically, each of these runs is angledabout 5 from a true lengthwise direction, making a total of between theruns themselves. By maintaining a 90 relationship between run 22 andcrossbar and between run 23 and crossbar 18, the intermediate openingsand 21 are divergent towards their open sides. These crossbars 15 and 18are to receive return bend portions 12B and 13B of the strap ends andthe resultant increased clearance at the free ends of the crossbars 15and 18 makes the buckle easier to thread. Another advantage of thearrangement of FIGURE 4, is that the crossbars 15 and 18 distort towardsa true transverse direction in response to cantilever forces actingthereon during tensioning and during subsequent strap holding. Thisoptimizes ultimate gripping of the strap.

In the other configuration shown in FIGURE 4A, the endwise runs 22 and23 are both directed in a true lengthwise direction along the buckle andare coplanar to appear congruent in plan outline.

To appreciate the increased holding power exhibited by the new bucklearrangement, it is helpful to consider the path of the strap ends whichare threaded through the buckle and for this purpose reference should behad to the enlarged view of FIGURE 5. For purposes of this discussion,it will be assumed that the strap end 12 is at the free end of a strapand that the strap end 13 is the supply end and is connected to a strapreel which is not shown. In this event, tension is pulled on the strapend 13 to the extent that it is necessary to draw the strap loop taut.Pulling final tension on a strap loop normally requires a mechanicalassist and some form of tensioning tool may be employed. It is normalfor the operator to be located on the same side as the supply strap end13 and connect the tool at that region of the strap for pulling the tooltowards him to draw the strap end through the buckle. For the straptensioning operation assumed herein, the left side of the buckle, asviewed by the operator, is the open side, in which case the strap may befed into the buckle by the operator grasping the buckle in his righthand and the strap in his left hand. After the strap loop is formedabout the package 10, the free strap end 12 is applied to the buckle byfolding the strap end double and passing the thus formed return bendportion 123 upwardly through the central buckle opening 19 and thenaround the intermediate crossbar 16 to an extent sufficient to permitthe return bend 12B to be looped about the crossbar 15. In an analogousfashion, the strap end 13 is formed double to present a return bendportion 13B which is fed upwardly through the central buckle opening 19and around the crossbar 17 to an extent suflicient to permit the returnbend portion 13B to be looped about crossbar 18.

The spacial positioning of the crossbars 15 to 18 in their paired setsis such that as tension is drawn on the strap loop, the crossbar 15presents a strap contacting surface over an arc of about 180, the crossbar 16 presents a strap contacting surface over an arc of about 270, thecrossbar 17 presents a strap contacting surface over an arc of about180, and the crossbar 18 also presents a strap contacting surface overan arc of about 180. These effective surface contacting regions areemphasized by heavy, solid line arcuate segments in FIGURE 5. In thecase of the free end of the strap, it will be noted that the tension onthe adjacent intraloop region of the strap acts to reinforce the contactbetween the crossbar 16 and the strap end 12 and in addition sets uppressurized contact between the adjacent overlapping portions of thestrap. Similarly, the intraloop region of the strap adjacent the supplyend 13 acts to reinforce the strap contacting pressure acting oncrossbar 17 and also acts to set up pressurized resistance to slippagebetween the overlapping portions of the strap as they pass about thecross bar 17. These effects are not realized to any comparable extent inany buckles employed prior to the development of the buckle of thisinvention, and a comparison of the effective strap contacting surfacespresented by the crossbars of the present buckle makes it clear thatsignificant improvements in holding power are actually achieved.

It is preferred to apply the buckle in the fashion described as thecrossbars 15 and 16 present a maximum strap gripping action and shouldtherefore be associated with the dead end of the strap. The crossbars 17and 18 produce somewhat less strap gripping action and therefore enablethe strap to be drawn through the buckle in a loop tensioning mode withgreater ease. It is possible and practical to use the buckle in areverse fashion wherein the strap end 13 may be considered the free end,and the strap end 12 may be considered the supply end which connects toa strap reel. In this case, the operator faces the strap end 12 andgrasps the buckle in his left hand, and grasps the strap in his righthand to feed it into the open righthand side of the buckle.

Thus, while preferred constructional features of the invention areembodied in the structure illustrated herein, it is to be understoodthat changes and variations may be made by those skilled in the artwithout departing from the spirit and scope of the appended claims.

What is claimed is:

1. A buckle formed of a single metal rod, said buckle being generallyrectangular in plan outline and having a set of strap engaging crossbarson opposite ends thereof, said sets of crossbars extending substantiallyside by side and the crossbars common to each set extendingsubstantially side by side, the first crossbar of one set constituting aterminal portion of the rod and defining one end extremity of the buckleoutline and the second crossbar of said one set constituting anintermediate section of the rod, the first crossbar of the other setconstituting an intermediate section of the rod and the second crossbarof said other set constituting an opposite terminal portion of the rodand defining an opposite end extremity of the buckle outline, said rodhaving an endwise r-un interconnecting the said first crossbars, andanother endwise run interconnecting the said second crossbars, saidendwise runs being partially overlapping and partially exposed in planoutline relation to each other, and said rod having an endwise runinterconnecting the second crossbar of said one set and the firstcrossbar of said second set.

2. A buckle formed of a single metal rod, said buckle being generallyrectangular in plan outline and having a set of strap engaging crossbarson opposite ends thereof, said sets of crossbars extending substantiallyparallel to each other and the crossbars common to each set extendingsubstantially parallel to each other, the first crossbar of one setconstituting a terminal portion of the rod and defining one endextremity of the buckle outline and the second crossbar of said one setconstituting an intermediate section of the rod, the first crossbar ofthe other set constituting an intermediate section of the rod and thesecond crossbar of said other set constituting an opposite terminalportion of the rod and constituting an opposite end extremity of thebuckle outline, said rod having a straight run interconnecting the saidfirst crossbars, and another straight run corresponding in length to thefirst named straight run and interconnecting the said second crossbars,said straight runs being partially overlapping and partially oxposed inplan outline relation to each other, and said rod having a straight runinterconnecting the second crossbar of said one set and the firstcrossbar of said second set.

3. A strap buckle constituted by a one-piece skeletal rod of generallyrectangular plan outline configuration and having first and second endsets of strap contacting crossbars, said sets of crossbars extendingsubstantially side by side and spaced endwise of the buckle to define acommon central opening for passage of opposite ends of a strap loop, thecrossbars of each set extending substantially side by side and spacedendwise to the buckle to define for each set a separate intermediateopening for passage of the corresponding strap end, the first crossbarof one set constituting a terminal portion of the rod and defining oneend extremity of the buckle outline and the second crossbar of said oneset constituting an intermediate section'of the rod, the first crossbarof the other set constituting an intermediate section of the rod and thesecond crossbar of said other set constituting an opposite terminalportion of the rod and defining an opposite end extremity of the buckleoutline, said rod having an endwise r-un interconnecting the said firstcrossbars, and another endwise run interconnecting the said secondcrossbars, said endwise runs having oppositely inclined lengthwisedirections in plan outline and being partially overlapping and partiallyexposed in plan outline relation to each other, and said rod having anendwise run interconnecting the second crossbar of said one set and thefirst crossbar of said second set.

4. A strap buckle constituted by a one-piece skeletal rod of generallyrectangular plan outline configuration and having first and second endsets of strap contacting crossbars, said sets of crossbars extendingsubstantially side by side and spaced endwise to the buckle to define acommon central opening for passage of opposite ends of a strap loop, thecrossbars of each set extending substantially side by side and spacedendwise of the buckle to define for each set a separate intermediateopening for passage of the corresponding strap end, the first crossbarof one set constituting a terminal portion of the rod and defining oneend extremity of the buckle outline and the second cross bar of said oneset constituting an intermediate section of the rod, the first crossbarof the other set constituting an intermediate section of the rod and thesecond crossbar of said other set constituting an opposite terminalportion of the rod and constituting an opposite end extremity of thebuckle outline, said rod having a straight run interconnecting the saidfirst crossbars, and another straight run corresponding in length to thefirst named straight run and interconnecting the said second crossbars,said straight runs lying in a common plane and being partiallyoverlapping and partially exposed in plan outline relation to eachother, and said rod having a straight run interconnecting the secondcrossbar of said one set and the first crossbar of said second set.

References Cited UNITED STATES PATENTS 1,012,402 12/ 1911 McFarland 24263,112,543 12/ 1963 Derrickson 24-26 X OTHELL M. SIMPSON, PrimaryExaminer. E. SIMONSEN, Assistant Examiner.

1. A BUCKLE FORMED OF A SINGLE METAL ROD, SAID BUCKLE BEING GENERALLYRECTANGULAR IN PLAN OUTLINE AND HAVING A SET OF STRAP ENGAGING CROSSBARSON OPPOSITE ENDS THEREOF, SAID SETS OF CROSSBARS EXTENDING SUBSTANTIALLYSIDE BY SIDE AND THE CROSSBARS COMMON TO EACH SET EXTENDINGSUBSTANTIALLY SIDE BY SIDE, THE FIRST CROSSBAR OF ONE SET CONSTITUTING ATERMINAL PORTION OF THE ROD AND DEFINING ONE END EXTREMITY OF THE BUCKLEOUTLINE AND THE SECOND CROSSBAR OF SAID ONE SET CONSTITUTING ANINTERMEDIATE SECTION OF THE ROD, THE FIRST CROSSBAR OF THE OTHER SETCONSTITUTING AN INTERMEDIATE SECTION OF THE ROD AND THE SECOND CROSSBAROF SAID OTHER SET CONSTITUTING AN OPPOSITE TERMINAL PORTION OF THE RODAND DEFINING AN OPPOSITE END EXTREMITY OF THE BUCKLE OUTLINE, SAID RODHAVING AN ENDWISE RUN INTERCONNECTING THE SAID FIRST CROSSBARS, ANDANOTHER ENDWISE RUN INTERCONNECTING THE SAID SECOND CROSSBARS, SAIDENDWISE RUNS BEING PARTIALLY OVERLAPPING AND PARTIALLY EXPOSED IN PLANOUTLINE RELATION TO EACH OTHER, AND SAID ROD HAVING AN ENDWISE RUNINTERCONNECTING THE SECOND CROSSBAR OF SAID ONE SET AND THE FIRSTCROSSBAR OF SAID SECOND SET.